X‐ray views of our solar system

The solar system comprises a relatively small number of X‐ray emitting objects, which are associated with a variety of physical emission processes: we can explore them with good spatial and temporal precision at relatively local distances, and in situ as well, unlike the rest of the Universe. Moreover, from the study of the solar system, we can gather insights into extra‐solar planets too. This article offers a review of our current knowledge of the X‐ray properties of bodies in our solar system, of the physical processes leading to X‐ray emissions, and of recent breakthrough discoveries brought about by space probes providing remote imaging as well as in situ measurements. In the long term, the next generation of Earth‐bound X‐ray observatories and the possibility of in situ X‐ray measurements, that is, by X‐ray telescopes onboard spacecraft visiting the planets, will underpin the next giant leap in discovery space.